I'm kind of interested too. So far, I think they all just have to comply to the PPPoE "standard" or something for the DSL network I'm on (PacBell <- SBC). I have a Westell WireSpeed DSL modem. Not sure exactly which physical DSL type, but ADSL is my initial guess.
You do need a hub if you are using ethernet RJ-45 connectors (looks like phone wires, only more wires and thicker, which you are already using). You can get by with a 10Base-2 network coaxial cable (not sure what the term is) and not use hubs, bit those are limited to 10Mbps half dulpex, and you need some terminators for the end "branches" of the network. I noticed NICs don't seem to offer both connector types very often nowadays, so this might not be an option.
I did once setup a cheap coax network with roomates, and the cheap hub was a bit too much for our budgets!